Possible gnat and ObjectAda bugs?

["David C. Hoos, Sr." <david.c.hoos.sr@ada95.com>]

The code at the end of this message produces strange results with GNAT
3.13p,
and even more bizarre results with ObjectAda 7.1:

What is strange is that when Standard Input is from the keyboard, the
program
does not enter the loop until the enter key has been pressed.

Is this a bug, or am I missing something here?

with Ada.Text_IO;
procedure Echo
is
   C : Character;
begin
   while not Ada.Text_IO.End_Of_File (Ada.Text_IO.Current_Input)
   loop
      Ada.Text_IO.Put_Line
        (Ada.Text_IO.Standard_Error,
         "Waiting for character...");
      Ada.Text_IO.Get_Immediate (C);
      Ada.Text_IO.Put_Line
        (Ada.Text_IO.Standard_Error,
         "Got character at position" &
         Integer'Image (Character'Pos (C)));
      Ada.Text_IO.Put (Ada.Text_IO.Current_Output, C);
   end loop;
end Echo;